Effective high frequency (HF) antennas, which are compatible with the varied and demanding requirements peculiar to military tactical communications, are by no means easily engineered. Military radios operate over a broadband (e.g., 3-30 MHZ) and vary in power from watts to kilowatts. The communication systems are often fixed, but must be transportable by vehicular, man-portable or airborne means and often necessitate ionospheric propagation over long range paths.
The required mobility would suggest small antenna size of light weight, but electrical performance will be compromised if the antenna is made too small in terms of the wavelength(s). The necessary broad frequency range which typically spans three octaves or more complicates the design of efficient antennas.
The conventional log-periodic dipole array (LPDA) generally offers good efficiency and broad bandwidth and has been used heretofore for military communication purposes. A commercially available log-periodic dipole antenna which has been utilized as the base station antenna for military communication purposes is the AS-317A/TSC-99 antenna made by Technology Communications International Co. (T.C.I.). While this antenna is satisfactory in the above-mentioned respects, it is unwieldy, difficult and time consuming to deploy, expensive, and because of its very large physical size the number of possible sites is restricted by political, economic, logistic, and other considerations (e.g., zoning approval).